Patent US2581810A successfully refreshed from Google Patents.
US2581810A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drum type, rotary, perpetual calendar
Assignee: Individual
•
Filing: 1946-07-16
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Granted: 1952-01-08
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Expires: 1966-07-16
Abstract
No abstract record available.
Inventors
- 👤 Edgar B Nichols
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:52
CPC Classifications
G; G09; G09D; G09D3/00; G09D3/04; G09D3/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1414686A
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US1433656A
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US1594259A
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US1801714A
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FR688643A
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US2110668A
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US2096248A
Cited
US2296551A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-01-07 | 1955-07-09 | 1956-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-01-07 | 1959-07-09 | 1960-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-01-07 | 1963-07-09 | 1964-01-08 | $7700.00 | Window Closed / Lapsed |